The Chief High Court judge has ordered a judicial review into a court's decision to allow Kim Dotcom to see copies of evidence seized from his house in January this year.
The German co-founder of the file-sharing site Megaupload is living in New Zealand where he has residency. He and three other men are facing extradition to the United States on charges of internet piracy and money laundering in what is described as the largest criminal copyright case in the world.
A District Court judge earlier allowed Mr Dotcom's defence team access to the copies, but the Crown appealed against it.
It argued for a judicial review, saying it would take more than two-and-a half months to copy all of the evidence in New Zealand, which would interfere with the extradition hearing.
Mr Dotcom's lawyer Willy Akel disputed that, saying they should start copying it straight away while they wait for an appeal on the earlier decision.
Justice Winkelmann says a judicial review, which will take two days, has been granted and ordered the Crown to start copying the material in the meantime.
Megaupload was indicted in a federal court in Virginia on 19 January this year and the site was shut down.
Kim Dotcom and his co-accused were arrested in Auckland, New Zealand, the following day.
Formal papers requesting their extradition were lodged by the US in March.